There is known an image forming apparatus capable of duplex printing, which comprises an image forming unit including a photoconductor and a transfer member, an exposure device for exposing the photoconductor to light, a sheet feeder unit for feeding a recording sheet to the image forming unit, sheet ejection rollers for ejecting the recording sheet having an image formed thereon by the image forming unit, a conveyance path for conveying the recording sheet, which extends from the sheet feeder unit to the sheet ejection rollers, passing through between the photoconductor and the transfer member of the image forming unit, and a re-conveyance path for conveying the recording sheet having passed through the image forming unit to a position upstream from the photoconductor in the conveyance path.
To be more specific, the sheet ejection rollers are configured to be rotatable in forward and reverse directions such that the recording sheet conveyed along the conveyance path is ejected outside the casing by the forward rotation of the sheet ejection rollers and that a traveling direction of the recording sheet is reversed, after the recording sheet partly protrudes outside the casing, by the reverse rotation of the sheet ejection rollers, whereby the recording sheet is retracted back into the casing. The re-conveyance path is configured such that the recording sheet of which the traveling direction has been reversed by the sheet ejection rollers is caused to pass through a space between the photoconductor and the exposure device and then conveyed to a position upstream from the photoconductor in the conveyance path.